Acetabular Labral Tear Dimensions and Number of Suture Anchors Used to Repair in Patients with Femoroacetabular Impingement Syndrome

Femoroacetabular impingement syndrome (FAIS) is commonly associated with acetabular labral tears. Correction of impingement morphology and suture anchor repair of labral tears have demonstrated successful early and midterm patient-reported outcomes. The purpose of this study was to evaluate the posterior and anterior extent and size of labral tears in patients with FAIS undergoing arthroscopic labral repair, and to evaluate the number of suture anchors required to repair these tears. The design of this study was retrospective case series (Level 4). A single surgeon's operative database was retrospectively reviewed to identify patients undergoing primary arthroscopic hip labral repair between November 2014 and September 2019. Patient-specific factors and radiographic measurements were recorded. Arthroscopic findings including labral tear posterior and anterior extents, and the number of suture anchors utilized for the repair were recorded. Linear regression was performed to identify factors associated with labral tear size. The number of suture anchors used relative to labral tear size was calculated. Three-hundred and thirteen patients were included in the study. The mean posterior and anterior extent for labral tears were 11:22 ± 52 and 2:20 ± 34 minutes, respectively. Mean tear size was 2 hours, 58 minutes ± 45 minutes. The mean number of suture anchors utilized for labral repair was 3.1 ± 0.7. The mean number of anchors per hour of labral tear was 1.1 ± 0.3. Increased age, lateral center edge angle, and α angle were associated with larger labral tears. Our study found that acetabular labral tears associated with FAIS are, on average, 3 hours in size and centered in the anterosuperior quadrant of the acetabulum. Arthroscopic labral repair required 1.1 anchors per hour of tear size, resulting in a mean of 3.1 anchors per repair. Level of Evidence IV

SOME THOUGHTS ON INTERSPECIFIC MANDIBULAR MORPHOLOGY IN FOSSIL AND MODERN ALLIGATOR

Alligator is diagnosed in the fossil record using discrete morphological characters. These characters are used with systematic analyses to determine hypothetical phylogenetic relationships. Examined here are two such characters for applicability in fossil species determination and relationship. One is the curvature of the dentary between the fourth and tenth alveoli (observed in several taxa), while the other is a further investigation into the anterior extent of the splenial (in modern Alligator mississippiensis and the early Pleistocene A. hailensis). In a small sample size, the curvature of the dentary exhibits wide variability in character states both intraspecifically and interspecifically, bringing into question its utility in fossil crocodylian systematic applications. The anatomy of the anterior extent of the splenial is phylogenetically informative, and a new method for inferring its presence as a basal or derived state (as a scar on the dentary) is described.

Phylogenetic position of Sphincterodiplostomum Dubois, 1936 (Digenea: Diplostomoidea) with description of a second species from Pantanal, Brazil

Sphincterodiplostomum is a monotypic genus of diplostomid digeneans that parasitize fish-eating birds in the neotropics. The type species Sphincterodiplostomum musculosum has a unique, dorsal, tubular invagination in the opisthosoma with a muscular sphincter. Whereas larvae of S. musculosum are relatively commonly reported in Neotropical fish helminth surveys, adult specimens from birds are rarely collected. Prior to our study, no DNA sequence data for S. musculosum were available. Our molecular and morphological study of mature and immature adult Sphincterodiplostomum specimens from three species of birds and one species of crocodilian revealed the presence of at least two species of Sphincterodiplostomum in the neotropics. We provide the first molecular phylogeny of the Diplostomoidea that includes Sphincterodiplostomum. In addition, this is the first record of S. musculosum from caimans, along with the first record of fully mature adult S. musculosum from green kingfisher Chloroceryle americana. The new species of Sphincterodiplostomum (Sphincterodiplostomum joaopinhoi n. sp.) can be morphologically distinguished from S. musculosum based on the anterior extent of vitelline follicles, narrower prosoma, substantially smaller holdfast organ and structure of tegumental spines. Our data revealed 0.7% interspecific divergence in 28S and 10.6–11.7% divergence in cox1 sequences between the two Sphincterodiplostomum species.

Fully Automated Delineation of the Optic Radiation for Surgical Planning using Clinically Accessible Sequences

Quadrantanopia caused by inadvertent severing of Meyer's Loop of the optic radiation is a well-recognised complication of temporal lobectomy for conditions such as epilepsy. Dissection studies indicate that the anterior extent of Meyer's Loop varies considerably between individuals. Quantifying this for individual patients is thus an important step to improve the safety profile of temporal lobectomies. Previous attempts to delineate Meyer's Loop using diffusion MRI tractography have had difficulty estimating its full anterior extent, required manual ROI placement, and/or relied on advanced diffusion sequences that cannot be acquired routinely in most clinics. Here we present CONSULT - a pipeline that can delineate the optic radiation from raw DICOM data in a completely automated way via a combination of robust preprocessing, segmentation, and alignment stages, plus simple improvements that bolster the efficiency and reliability of standard tractography. We tested CONSULT on 694 scans of predominantly healthy participants (538 unique brains), including both advanced acquisitions and simpler acquisitions that could be acquired in clinically acceptable timeframes. Delineations completed without error in 99.4% of the scans. The distance between Meyer's Loop and the temporal pole closely matched both averages and ranges reported in dissection studies for all tested sequences. Median scan-rescan error of this distance was 1mm. When tested on two participants with considerable pathology, delineations were successful and realistic. Through this, we demonstrate not only how to identify Meyer's Loop with clinically accessible sequences, but also that this can be achieved without fundamental changes to tractography algorithms or complex post-processing methods.

Enhancing Image Characteristics of Retinal Images of Aggressive Posterior Retinopathy of Prematurity Using a Novel Software, (RetiView)

Purpose. To report pilot data from a novel image analysis software “RetiView,” to highlight clinically relevant information in RetCam images of infants with aggressive posterior retinopathy of prematurity (APROP).Methods. Twenty-three imaging sessions of consecutive infants of Asian Indian origin with clinically diagnosed APROP underwent three protocols (Grey Enhanced (GE), Color Enhanced (CE), and “Vesselness Measure” (VNM)) of the software. The postprocessed images were compared to baseline data from the archived unprocessed images and clinical exam by the retinopathy of prematurity (ROP) specialist for anterior extent of the vessels, capillary nonperfusion zones (CNP), loops, hemorrhages, and flat neovascularization.Results. There was better visualization of tortuous loops in the GE protocol (56.5%); “bald” zones within the CNP zones (26.1%), hemorrhages (13%), and edge of the disease (34.8%) in the CE images; neovascularization on both GE and CE protocols (13% each); clinically relevant information in cases with poor pupillary dilatation (8.7%); anterior extent of vessels on the VNM protocol (13%) effecting a “reclassification” from zone 1 to zone 2 posterior.Conclusions. RetiView is a noninvasive and inexpensive method of customized image enhancement to detect clinically difficult characteristics in a subset of APROP images with a potential to influence treatment planning.

Champsosaurus (Diapsida: Choristodera) from the Paleocene of west Texas: paleoclimatic implications

A specimen of the aquatic reptile Champsosaurus sp. from the Paleocene Black Peaks Formation in southwestern Texas is the southernmost yet known. the fragmentary specimen exhibits some unusual features, such as a great anterior extent of the quadratojugal on the lower temporal arch, and cannot be attributed with confidence to any of the named species. Champsosaurus appears to have been tolerant of temperate climates and had a northern latitudinal range exceeding that of crocodylians. It seems likely that the brief southward extension in range of Champsosaurus during early Paleocene time resulted from a decrease in mean annual temperature, comparable to over 10° of paleolatitude.

Mechanics of Embryonic Head Fold Morphogenesis

Head fold morphogenesis constitutes the first discernible epithelial folding event in the embryonic development of the chick. It arises at Hamburger and Hamilton (HH) stage 6 (approximately 24 hours into a 21-day incubation period) and establishes the anterior extent of the embryo [1]. At this stage, the embryonic blastoderm is composed of three germ layers (endoderm, mesoderm, and ectoderm), which are organized into a flat layered sheet that overlies the fibrous vitelline membrane (VM). Within this blastodermal sheet, a crescent-shaped head fold develops just anterior to the elongating notochord, spanning across the embryonic midline at the rostral end of neural plate. At the crest of this fold, the bilateral precardiac plates fuse in a cranial to caudal direction and give rise to the primitive heart tube and foregut [2, 3]. An understanding of head fold morphogenesis may thus offer insight into how embryonic tissues are arranged to make ready for proper cardiac formation.

Radiographic Location of the Lateral Intercondylar Ridge

Background The lateral intercondylar ridge (resident's ridge) is considered to be an important landmark during anterior cruciate ligament reconstruction. Presently, no study exists describing the location of this vital landmark on plain radiographic images. Hypothesis Lateral intercondylar ridge location can be estimated on lateral plain film images. Study Design Descriptive laboratory study. Methods Lateral radiographic images were taken of 20 distal femora with metallic markers overlying the lateral intercondylar ridge. The length of Blumensaat's line and the distance from the anterior extent of Blumensaat's line to the point where the lateral intercondylar ridge intersects Blumensaat's line were measured. The ratio of these measurements was then determined (Blumensaat's-ridge ratio). The angle of the lateral intercondylar ridge with respect to Blumensaat's line (Blumensaat's-ridge angle) was also determined. Results The mean length of Blumensaat's line was 32.1 mm (95% confidence interval, 31.0–33.2 mm). The mean distance from the anterior extent of Blumensaat's line to the point where the lateral intercondylar ridge intersects Blumensaat's line was 25.3 mm (95% confidence interval, 24.3–26.3 mm). The mean Blumensaat's-ridge ratio was 0.79 (95% confidence interval, 0.77–0.81). The mean Blumensaat's-ridge angle was 75.5° (95% confidence interval, 72.0°–79.1°). Conclusion The lateral intercondylar ridge intersects Blumensaat's line at a point defined by multiplying the Blumensaat's line length by 0.79. From this point, the ridge runs at a 75.5° angle with respect to Blumensaat's line. Clinical Relevance Awareness of the radiographic location of the lateral intercondylar ridge may help confirm accurate tunnel placement when arthroscopic positioning is in doubt. Furthermore, femoral tunnel position can be quickly and accurately assessed in the outpatient setting in patients with unsatisfactory outcomes after anterior cruciate ligament reconstruction.